1. Field of the Invention
The present invention is directed toward the field of replicating information from a host system where the information is normally stored to a mobile data communication device. In particular, the system and method of the present invention provide an event-driven redirection computer program (xe2x80x9credirector programxe2x80x9d) operating at the host system, which, upon sensing a particular user-defined event has occurred, redirects user-selected data items, such as calendar event messages, from the host system to the user""s mobile data communication device. The mobile data communication device is preferably coupled to the host system via a wireless network and one or more landline networks. Due to the bandwidth limitations of wireless networks, only a portion of a user-selected data item is generally redirected to the user""s mobile device, with the user given the option of then retrieving the entire data item (or some other portion of the data item) from the host system.
Instead of warehousing (or storing) the user""s data items at the host system and then xe2x80x9csynchronizingxe2x80x9d the mobile data communication device to data items stored at the host system when the mobile device requests that such items of information be communicated to it, the present invention employs a xe2x80x9cpushxe2x80x9d paradigm that continuously packages and retransmits the user-selected items of information to the mobile data communication device in response to a triggering event detected at the host system. Wireless mobile data communications devices, especially those that can return a confirmation signal to the host that the pushed data has been received are especially well suited for this type of push paradigm.
2. Description of the Related Art
Present systems and methods for replicating information from a host system to a user""s mobile data communication device are typically xe2x80x9csynchronizationxe2x80x9d systems in which the user""s data items are warehoused (or stored) at the host system for an indefinite period of time and then transmitted in bulk only in response to a user request. In these types of systems and methods, when replication of the warehoused data items to the mobile device is desired, the user typically places the mobile device in an interface cradle that is electrically connected to the host system via some form of local, dedicated communication, such as a serial cable or an infrared or other type of wireless link. Software executing on the mobile data communication device then transmits commands via the local communications link to the host system to cause the host to begin transmitting the user""s data items for storage in a memory bank of the mobile device. In these synchronization schemes, the mobile unit xe2x80x9cpullsxe2x80x9d the warehoused information from the host system in a batch each time the user desires to replicate information between the two devices. Therefore, the two systems (host and mobile) only maintain the same data items after a user-initiated command sequence that causes the mobile device to download the data items from the host system.
A general problem with these xe2x80x9csynchronizationxe2x80x9d systems is that the only time that the user data items are replicated between the host system and the mobile data communication device is when the user commands the mobile device to download or pull the user data from the host system. Five minutes later a new message could be sent to the user, but the user would not receive that message until the next time the user fetches the user data items. Thus, a user may fail to respond to an emergency update or message because the user only periodically synchronizes the system, such as once per day.
Other problems with these systems include: (1) the amount of data to be reconciled between the host and the mobile device can become large if the user does not xe2x80x9csynchronizexe2x80x9d on a daily or hourly basis, leading to bandwidth difficulties, particularly when the mobile device is communicating via a wireless packet-switched network; and (2) reconciling large amounts of data, as can accrue in these batch-mode synchronization systems, can require a great deal of communication between the host and the mobile device, thus leading to a more complex, costly and energy-inefficient system.
A more automated, continuous, efficient and reliable system of ensuring that user data items, such as calendar messages, are replicated at the user""s mobile device is therefore needed.
Calendar event messages, such as meeting requests, are typically organized according to a particular calendar data structure. For example, RFC2445 (iCalendar), also referred to as ICAL, provides such a structure and standard method for defining calendar-related data messages. When combined with RFC2446 (iTIP), which defines a transport independent means for exchanging ICAL objects, a mechanism is provided to allow calendar systems on multiple platforms to inter-operate.
ICAL uses verbose text strings and values to represent electronic calendar data. The RFC 2445 standard for structuring ICAL messages does not make any attempt to reduce the size of the control information passed in the ICAL message. According to this known calendar message standard, message size is not as important as is readability of the message contents. The problem with using standards, such as ICAL, relates to sending calendar event messages over narrow bandwidth channels, like a wireless packet data network. In such a network, it is critical to reduce the size of the message as much as possible.
Therefore, there is a need for a system and method for sending and receiving and structuring calendar event messages, such as meeting requests, to and from a portable data communication devices over a wireless data network.
Furthermore, there remains a general need in this art for a system and method of continuously pushing user-selected data items (or certain portions of the selected data items), such as calendar event messages, stored at a host system to a user""s mobile data communication device.
There remains a more particular need for such a system and method where user-selected data items are continuously xe2x80x9cpushedxe2x80x9d from the host system to the mobile data communication device upon the occurrence of one or more user-defined triggering events.
There remains an additional need for such a system and method that provides flexibility in the types and quantities of user data items that are pushed from the host system to the mobile data communication device and that also provides flexibility in the configuration and types of events that can serve to trigger the redirection of the user data items.
There remains yet an additional need for such a system and method that can operate locally on a user""s desktop PC or at a distance via a network server.
There remains still another need for such a system and method that provides for secure, transparent delivery of the user-selected data items from the host system to the mobile device.
The present invention overcomes the problems noted above and satisfies the needs in this field for a system and method of pushing user-selected data items from a host system to a user""s mobile data communication device upon detecting the occurrence of one or more user-defined event triggers. As used in this application, the term host system refers to the computer where the redirector software is operating. In the preferred embodiment of the present invention, the host system is a user""s desktop PC, although, alternatively, the host system could be a network server connected to the user""s PC via a local-area network (xe2x80x9cLAN)xe2x80x9d, or could be any other system that is in communication with the user""s desktop PC.
A redirector program operating at the host system enables the user to redirect or mirror certain user-selected data items (or parts of data items) from the host system to the user""s mobile data communication device upon detecting that one or more user-defined triggering events has occurred. Also operating at the host system are various sub-systems that can be configured to create triggering events, such as a screen saver sub-system or a keyboard sub-system, as well as sub-systems for repackaging the user""s data items for transparent delivery to the mobile data device, such as a TCP/IP sub-system or one or more E-Mail sub-systems. Other sub-systems for creating triggering events and repackaging the user""s data items could also be present at the host system. The host system also includes a primary memory store where the user""s data items are normally stored.
Using the redirector program, the user can select certain data items for redirection, such as E-mail messages, calendar events, meeting notifications, address entries, journal entries, personal reminders etc. Having selected the data items for redirection, the user can then configure one or more event triggers to be sensed by the redirector program to initiate redirection of the user data items. These user-defined trigger points (or event triggers) include external events, internal events and networked events. Examples of external events include: receiving a message from the user""s mobile data communication device to begin redirection; receiving a similar message from some external computer; sensing that the user is no longer in the vicinity of the host system; or any other event that is external to the host system. Internal events could be a calendar alarm, screen saver activation, keyboard timeout, programmable timer, or any other user-defined event that is internal to the host system. Networked events are user-defined messages that are transmitted to the host system from another computer coupled to the host system via a network to initiate redirection. These are just some of the examples of the types of user-defined events that can trigger the redirector program to push data items from the host to the mobile device. Although in the preferred embodiment it is anticipated that the configuration that specifies which data items will be redirected and in what form will be set at the host system, it is within the scope of this invention that such configuration may be set or modified through data sent from the mobile communications device.
In addition to the functionality noted above, the redirector program provides a set of software-implemented control functions for determining the type of mobile data communication device and its address, for programming a preferred list of message types that are to be redirected, and for determining whether the mobile device can receive and process certain types of message attachments, such as word processor or voice attachments. The determination of whether a particular mobile device can receive and process attachments is initially configured by the user of that mobile device at the host system. This configuration can be altered on a global or per message basis by transmitting a command message from the mobile device to the host system. If the redirector is configured so that the mobile data device cannot receive and process word processor or voice attachments, then the redirector routes these attachments to an external machine that is compatible with the particular attachment, such as an attached printer or networked fax machine or telephone. Other types of attachments could be redirected to other types of external machines in a similar fashion, depending upon the capabilities of the mobile device. For example, if a user is traveling and receives a message with an attachment that the user""s mobile device can process or display, the user may from a mobile communications device send a command message to the host system indicating that that attachment is to be sent to a fax machine at a hotel where the user will be spending the evening. This enables the user to receive important E-mail attachments as long as the host system is provided with sufficient information about the destination where the attachment is to be forwarded.
Once an event has triggered redirection of the user data items, the host system then repackages these items in a manner that is transparent to the mobile data communication device, so that information on the mobile device appears similar to information on the user""s host system. The preferred repackaging method includes wrapping the user data items in an E-mail envelope that corresponds to the address of the mobile data communication device, although, alternatively, other repackaging methods could be used with the present invention, such as special-purpose TCP/IP wrapping techniques, or other methods of wrapping the user selected data items. The repackaging preferably results in E-mail messages generated by the user from the mobile device to be transmitted from the host system, thus enabling the user to appear to have a single E-mail address, such that the recipients of messages sent from the mobile communications device do not know where the user was physically located when the message was first sent. The repackaging also permits both messages to the mobile device and sent from the mobile device to be encrypted and decrypted as well as compressed and decompressed.
In an alternative system and method, the redirector program executes on a network server, and the server is programmed to detect numerous redirection event triggers over the network from multiple user desktop computers coupled to the server via a LAN. The server can receive internal event triggers from each of the user desktops via the network, and can also receive external event triggers, such as messages from the users"" mobile data communication devices. In response to receiving one of these triggers, the server redirects the user""s data items to the proper mobile data communication device. The user data items and addressing information for a particular mobile device can be stored at the server or at the user""s PC. Using this alternative configuration, one redirector program can serve a plurality of users. This alternative configuration could also include an internet- or intranet-based redirector program that could be accessible through a secure webpage or other user interface. The redirector program could be located on an Internet Service Provider""s system and accessible only through the Internet.
In another alternative configuration of the present invention, a redirector program operates at both the host system and at the user""s mobile data communication device. In this configuration, the user""s mobile device operates similarly to the host system described below, and is configured in a similar fashion to push certain user-selected data items from the mobile device to the user""s host system (or some other computer) upon detecting an event trigger at the mobile device. This configuration provides two-way pushing of information from the host to the mobile device and from the mobile device to the host.
Another aspect of the invention provides a new data structure for calendar events. The structure is based on a standard calendar data structure, such as ICAL. However, unlike the ICAL structure, which utilizes text strings that are long and verbose, the present invention provides a compressed data structure (referred to herein as xe2x80x9cCICALxe2x80x9d) that uses numerical tags to represent the text strings. Because these numerical tags are much shorter in length then the long and verbose text strings in ICAL, the calendar event message can be effectively compressed, which is particularly useful when transferring calendar event messages over wireless data networks.
Another aspect of the invention provides a system for sending and receiving meeting requests on a portable data communication device. The system comprises: a host system coupled to a host calendar, wherein the host calendar stores calendar data records; a portable data communication device coupled to a device calendar, wherein the device calendar stores calendar data records; a network coupling the host system to the portable data communication device; software operating at the host system for updating a calendar data record and for generating a meeting request that is transmitted to the device; and software operating at the portable data communication device for accepting and generating meeting requests.
Another aspect of the invention provides a method for receiving meeting requests via a portable communication device. The method includes the steps of: (i) a meeting request arriving at the host, (ii) the host sending the meeting request to a redirector application, (iii) the redirector application converting the meeting request into an e-mail with an attachment containing the meeting details, (iv) the redirector application sending to the device the e-mail with the attachment, (v) the device opening the attachment, (vi) the user of the device accepting or declining the meeting request, (vii) sending a response in an e-mail with an attachment containing the reply, and (viii) converting the e-mail into a meeting response item and sending the meeting response item to the original sender of the meeting request.
Another aspect of the invention provides a method for sending meeting requests from a portable data communication device comprising the steps of: (i) creating a meeting request on the device, (ii) translating the meeting request to an e-mail with a CICAL attachment, (iii) sending the e-mail to the redirector, (iv) the redirector processing the CICAL attachment, (v) sending the meeting request to the host, (vi) the host sending the meeting requests to the attendees.
The primary advantage of the present invention is that it provides a system and method for triggering the continuous and real-time redirection of user-selected data items from a host system to a mobile data communication device. Other advantages of the present invention include: (1) flexibility in defining the types of user data to redirect, and in defining a preferred list of message types that are to be redirected or preferred senders whose messages are to be redirected; (2) flexibility in configuring the system to respond to numerous internal, external and to networked triggering events; (3) transparent repackaging of the user data items in a variety of ways such that the mobile data communication device appears as though it were the host system; (4) integration with other host system components such as E-mail, TCP/IP, keyboard, screen saver, webpages and certain programs that can either create user data items or be configured to provide trigger points; and (5) the ability to operate locally on a user""s desktop system or at a distance via a network server.
These are just a few of the many advantages of the present invention, as described in more detail below. As will be appreciated, the invention is capable of other and different embodiments, and its several details are capable of modifications in various respects, all without departing from the spirit of the invention. Accordingly, the drawings and description of the preferred embodiments set forth below are to be regarded as illustrative in nature and not restrictive.